1. Field of the Invention
The present invention relates to an improvement in a fluid coking process.
2. Description of the Prior Art
The fluid coking process is a well known process and is disclosed in U.S. Pat. No. 2,881,130, the teachings of which are hereby incorporated by reference. Integrated fluid coking and coke gasification processes are also known and disclosed, for example, in U.S. Pat. Nos. 3,661,543 and 3,816,084, the teachings of which are hereby incorporated by reference.
The present invention is applicable to conventional fluid coking processes as well as to integrated fluid coking and coke gasification processes.
It is known to use hot coking reactor vapors to lift the 700.degree. to 925.degree. F. portion of atmospheric residuum overhead with a coking reactor product and to feed the 925.degree. F.+ bottoms portion directly to the coking reactor as disclosed by Bush, R. A. in Oil and Gas Journal, April 6, 1970, page 110.
U.S. Pat. No. 3,144,400 discloses a fluid coking process in which whole petroleum crude oil is introduced into the scrubbing section with products from the coking vessel. Bottoms from the scrubbing section form the heavy oil feed going to a coking vessel.
It has now been found that a fluid coking process in which a hydrocarbonaceous oil is fed to the scrubber of the coker vapor product and in which the scrubber bottoms fraction is passed to a vacuum distillation zone will result in certain advantages such as reduction in the size of the vacuum pipestill, energy savings, increased liquid yields and other advantages that will become apparent in the ensuing description.